The present invention generally relates to a mesoporous composite powder or thin film having a three-dimensional structure with regularly arranged mesopores and having nanocrystalline metal oxide—glass in the porous structure framework; the manufacturing method thereof; a lithium battery, lithium intercalation electric device, photocatalytic device, solar battery, energy storage device and rechargeable battery as the specific applications thereof; in particular to a secondary battery having a nanocrystal oxide—glass mesoporous composite electrode material to be used as an electrode of a lithium battery.
Although application of a metal oxide mesoporous material in an electronic material, catalyst material, functional ceramic material and electrode material by having a three-dimensional structure with regularly arranged nanopores and a high specific surface area is expected, the current situation is that it is not possible to elicit the crystalline functions since the metal oxide in the framework is amorphous.
Further, groups worldwide are attempting various methods, but the nanostructure that is regularly arranged three-dimensionally will be crushed when metal oxide is subject to crystal growth in a nano-order framework, and there has been no successful experience heretofore.
There has been success in synthesizing MCM41 (hexagonal) and MCM48 (cubic) mesoporous silica (SiO2) powder with a surface active agent as the template (refer to Documents 1 and 2). Nevertheless, the current situation is that there has been no further technical advancement since then.
Further, today, metal oxide is frequently used as the active material for both the positive electrode and negative electrode of lithium batteries; in particular, rechargeable (secondary) lithium batteries on a worldwide scale of 10 trillion JPY.
Conventional metal oxide as the active material has a large particle size, and, since the electronic conductive path and ionic conductive path demanded in high-speed secondary batteries do not coexist, it is difficult to achieve a high rate of charging/discharging.
In order to improve the performance of batteries, miniaturization of particles or pores and enlargement of the specific surface area are demanded. Nevertheless, the current situation is that the various miniaturization methods proposed to date are not able to realize stable, high capacity under high rate charging/discharging conditions.
As a result, synthesis of metal oxide having high reversible capacity and superior cycle characteristics even at a high charging or discharging rate is desired.
As an example of a metal oxide material, there is mesoporous metal oxide. This mesoporous metal oxide having regularly arranged pores was reported in 1998 by Stucky et al (refer to Non-Patent Document 3).
Nevertheless, since these mesoporous metal oxides are amorphous, there is a problem in that it lacks stability as an electrode material. Applicant has succeeded in synthesizing nanocrystal oxide—glass mesoporous composite in 2004 (refer to Non-Patent Document 4 and Patent Document 1).
This nanocrystal oxide—glass mesoporous composite attracted much attention, and application as a catalyst carrier or dye-sensitized solar battery, lithium storage material, electrochemical dual-layer capacitor (EDLCs) has been proposed.    [Non-Patent Document 1] C. T. Kresge, M. E. Leonowicz, W. J. Roth, J. C. Vartuli, J. S. Beck, Nature 1992, 359, 710.    [Non-Patent Document 2] J. S. Beck, J. C. Vartuli, W. J. Roth, M. E. Leonowicz, C. T. Kresge, K. D. Schmitt, C. T.-W. Chu, D. H. Olson, E. W. Sheppard, S. B. McCullen, J. B. Higgins, J. L. Schlenker, Journal American Chemical Society. 1992, 114, 10834.    [Non-Patent Document 3] P. Yang, D. Zhao, D. I. Margolese, B. F. Chmelka, G. D. Stucky, Nature, 1998, 396, 152    [Non-Patent Document 4] D. Li, H. Zhou, I. Honma, Nature Materials, 2004, 3, 65    [Patent Document 1] Japanese Patent Application No. 2003-386694